Bill Benter faced restrictions or bans from Las Vegas casinos for card counting, but he and Alan Woods transitioned to Hong Kong horse racing, starting their collaboration around 1984 and establishing a horse racing model with about $150,000 in capital.

The first Hong Kong season did not see immediate success. By the summer of 1986, the duo had lost $120,000 of their initial $150,000 capital; their partnership subsequently broke down due to funding disputes. Benter returned to Hong Kong to independently improve the model, later recalling that his first profitable year earned about $600,000.

His cumulative profits have been described by the media as approaching $1 billion, but this is a long-term estimate and should not be considered as audited, publicly disclosed official profit figures. Benter's advantage cannot be reduced to "betting when the expected value is greater than zero"; rather, it lies in continuously building, testing, and calibrating win probability estimates.

Benter's model uses regression and programmatic calculations to convert variables such as track conditions, horse performance, rest days, and jockeys into probability estimates for each horse. He traveled to the UK to seek historical weather data for Hong Kong, testing and concluding that temperature had no significant predictive power and thus discarded it; effective features must be validated through out-of-sample performance, not just retained because they "seem reasonable".

His key idea is to integrate fundamental models with the implied probabilities of the betting market. The paper refers to the former as a fundamental handicapping model, converting market odds into public implied probabilities, and then testing whether the model provides incremental explanatory power relative to the market; this means he did not view the market as inefficient but sought verifiable biases based on the information already aggregated by the market.

Mechanically, Hong Kong horse racing operates on a pari-mutuel betting pool: bettors do not wager directly against a fixed bookmaker at locked odds, but rather enter a pooled fund after deductions, with final odds changing according to the flow of funds. Benter's team's buying would alter the prices within the pool, thus they had to simultaneously predict race outcomes, market probabilities, and the impact of their own bets on the odds; the beneficiaries are those who can estimate probabilities with lower error and control their positions, while the pressured parties are those betting based on narratives, intuition, or lagging information.

Source: Public information